add DISABLE_LTO_SUPPORT option

Conflicts:
	cctools/autogen.sh
cctools: make is_llvm_bitcode() more portable (fixes -flto with multiple -arch flags)
ld64: use faster strlcpy()/strlcat() "helper" implementations
ld64: fix qsort_r() helper function
fix emulated _NSGetExecutablePath() for FreeBSD
fix -luuid linkage issue on FreeBSD 10